While it used to come down essentially to the Audi or the Benz, the market has exploded with new choices. It's a field of force-fed V8s (twin-turbos all except the supercharged Jag) with between 520 and 550 hp, about 500 lb-ft of torque, and a 0-60 time in the fours.

Then, there's the new Mercedes S63 AMG. Sure, it's got a twin-turbo V8 like the others, but at 5.5 liters, it's bigger and packs more muscle, with 577 hp and 664 lb-ft of torque. Now driving through all four wheels, AMG is quoting a 3.9-second 0-60 time. That's only a tick quicker than the Audi, but is a few ahead of the rest of the cars in its class.

The increased performance (and reduced-fuel-consumption claim) comes down in part to the 220 pounds the S63 shed, thanks largely to its aluminum construction. Shifting is handled by the seven-speed automatic, while the 4MATIC system will channel up to two-thirds of the torque to the rear wheels as it rockets to an electronically-limited top speed of 186 mph.

Bigger wheels and an aero kit are expected to differentiate the big Benz from its less-AMG'd siblings. But it has the performance we came for, and that's the most important part.